In the market for tufted articles such carpet, there has been a substantial demand placed on the development of new production of new and innovative carpet patterns or styles to keep up with changing consumer tastes and increased competition in the market place. Control systems have now been developed for tufting machines that enable greater precision and variety in the design and production of tufted patterned carpets and other articles. For example, U.S. Pat. Nos. 8,141,505 and 8,359,989 disclose yarn placement and/or stitch distribution control systems for controlling the operation of a tufting machine to enable the placement of desired stitches or tufts of yarn, including selected colors or types of yarns, within a pattern being tufted into a backing material with enhanced precision, enabling a variety of patterned visual effects to be formed. Controls for yarn feed mechanisms or pattern attachments, such as single or double end yarn feed controls for controlling the feeding of 1-2 yarns to the needles of a tufting machine, further have been developed to provide control of individual yarns fed to each of the needles of the tufting machine. Such single or double end yarn feed attachments typically include a number of drive motors each driving a series of yarn feed rolls through which one or two ends of yarns can be fed to provide more individualized control of the feeding of the yarns to needles.
While such single or double end yarn feed mechanisms can provide more individualized control of each of the yarns being fed to the needles of a tufting machine, they typically are more expensive than standard yarn feed mechanisms or attachments. In addition, it is important that the yarn feed rolls of such systems be able to consistently feed the yarns over a desired useful life. As the yarn feed rolls are operated, however, they can be subjected to friction and other forces as the yarns pass thereover, which cause the rolls to become worn, which, in turn, can allow the yarns to slip or otherwise can result in a loss of control of the feeding of the yarns, generally requiring replacement of the yarn feed rolls. When such yarn feed rolls need to be replaced, the operation of the tufting machine typically will need to be halted, and individual yarn feed drives and/or devices often must be removed to enable access and replacement of the worn yarn feed rolls.
Accordingly, it can be seen that a need exists for a drive system such as for the yarn feed of a tufting machine that addresses the foregoing and other related and non-related problems in the art.